Gradation recording heat-transfer sheet

Claim 2

A gradation recording heat-transfer sheet comprising a support and, provided thereon, a heat-meltable ink layer containing a heat-meltable dye, which is characterized by being such that said heat-meltable ink layer further contains a saturated linear polyester; said heat-meltable dye has a melting point of 60°-120° C.; said heat-meltable dye content of said heat-meltable ink layer is 41-73% by weight in terms of solids based on total weight of the heat-meltable ink layer; and the ratio of said heat-meltable dye to said saturated linear polyester is 0.7-2.6:1.

Claim 3

A heat-transfer sheet according to claim 1, wherein the heat-meltable ink layer further contains gallic acid and/or a derivative thereof.

Claim 4

A heat-transfer sheet according to claim 2, wherein the heat-meltable ink layer further contains an acetylene glycol.

Claim 5

A heat-transfer sheet according to claim 1, wherein the heat-meltable dyes include at least yellow, magenta, and cyan dyes and the heat-meltable ink layers containing these dyes are coated in a localized pattern on the same support.

Claim 6

A heat-transfer sheet according to claim 1, wherein the heat-meltable dyes include at least yellow, magenta, cyan, and black dyes and the heat-meltable ink layers containing these dyes are coated in a localized pattern on the same support.

Claim 7

A gradation recording heat-transfer sheet comprising a support and, provided thereon, a heat-meltable ink layer containing a colored dye and/or a pigment, a non-wax binder, a saturated linear polyester, and a wax, which is characterized by being such that said heat-meltable ink layer further contains galllic acid and/or at least one derivative of gallic acid selected from methyl gallate, ethyl gallate, propyl gallate, isoamyl gallate, octyl gallate, lauryl gallate, stearyl gallate, trimethoxygallic acid, methyl trimethoxygallate, gallic acid 3-methyl ether, gallic acid 4-methyl ether, gallic acid 3,4-dimethyl ether, and gallic acid 3,5-dimethyl ether in an amount of 5-50% by weight in terms of solids based on the total weight 9 of the heat-meltable ink layer, and an acetylene glycol in an amount of 0.1-20% by weight in terms of solids based on the total weight of the heat-meltable ink layer.

Claim 8

A gradation recording heat-transfer sheet comprising a support and, provided thereon, a heat-meltable ink layer containing a colored dye and/or a pigment, a non-wax binder, a saturated linear polyester, and a wax, which is characterized by being such that said heat-meltable ink layer further contains galllic acid and/or at least one derivative of gallic acid selected from methyl gallate, ethyl gallate, propyl gallate, isoamyl gallate, octyl gallate, lauryl gallate, stearyl gallate, trimethoxygallic acid, methyl trimethoxygallate, gallic acid 3-methyl ether, gallic acid 4-methyl ether, gallic acid 3,4-dimethyl ether, and gallic acid 3,5-dimethyl ether in an amount of 5-50% by weight in terms of solids based on the total weight 9 of the heat-meltable ink layer, and an acetylene glycol in an amount of 0.1-20% by weight in terms of solids based on the total weight of the heat-meltable ink layer.

Claim 9

A heat-transfer sheet according to claim 6, wherein the acetylene glycol is at least one compound selected from 2,4,7,9-tetramethyl-5-decyne-4,7-diol, an ethylene oxide adduct thereof, and 3,6-dimethyl-4-octyne-3,6-diol.

Claim 10

A heat transfer sheet according to claim 6, wherein the ink layer further contains ethyl gallate or lauryl gallate.